APW7136B

APW7136A/B/C 1MHz, High-Efficiency, Step-Up Converter for 2 to 8 White LEDs Features Wide Input Voltage from 2.7V to 6V 0.25V Reference Voltage Fixed 1MHz Switching Frequency High Efficiency up to 87% www.DataSheet4U.com 100Hz to 100KHz PWM brightness control frequency General Description The APW7136A/B/C is a current-mode and fixed frequency boost converter with an integrated N-FET to drive up to 8 white LEDs in series. The series connection allows the LED current to be identical for uniform brightness. Its low on-resistance of NFET and feedback voltage reduce power loss and achieves high efficiency. Fast 1MHz current-mode PWM operation is available for input and output capacitors and a small inductor while minimizing ripple on the input supply. The OVP pin monitors the output voltage and stop switching if exceeds the over-voltage threshold. An internal soft-start circuit eliminates the inrush current during start-up. The APW 7136A/B/C also integrates under-voltage lockout, over-temperature protection and current limit circuits. The APW7136/A/B/C is available in a SOT-23-6 package. Open-LED Protection Under Voltage Lockout Protection Over Temperature Protection <1µA Quiescent Current during Shutdown SOT-23-6 Package Lead Free Available (RoHS Compliant) Applications White LED Display Backlighting Cell Phone and Smart Phone PDA, PMP, MP3 Digital Camera Simplified Application Circuit VIN C1 4.7µF 2 L1 22µH 6 VIN GND EN LX OVP FB 1 5 3 R1 12Ω ...